RESUMO
OBJECTIVE: Angiotensin-(1-7) [Ang-(1-7)] is a pro-resolving mediator. It is not known whether the pro-resolving effects of Ang-(1-7) are sustained and protect the lung from a subsequent inflammatory challenge. This study sought to investigate the impact of treatment in face of a second allergic or lipopolysaccharide (LPS) challenge. METHODS: Mice, sensitized and challenged with ovalbumin (OVA), received a single Ang-(1-7) dose at the peak of eosinophilic inflammation, 24 h after the final OVA challenge. Subsequently, mice were euthanized at 48, 72, 96, and 120 h following the OVA challenge, and cellular infiltrate, inflammatory mediators, lung histopathology, and macrophage-mediated efferocytic activity were evaluated. The secondary inflammatory stimulus (OVA or LPS) was administered 120 h after the last OVA challenge, and subsequent inflammatory analyses were performed. RESULTS: Treatment with Ang-(1-7) resulted in elevated levels of IL-10, CD4+Foxp3+, Mres in the lungs and enhanced macrophage-mediated efferocytic capacity. Moreover, in allergic mice treated with Ang-(1-7) and then subjected to a secondary OVA challenge, inflammation was also reduced. Similarly, in mice exposed to LPS, Ang-(1-7) effectively prevented the lung inflammation. CONCLUSION: A single dose of Ang-(1-7) resolves lung inflammation and protect the lung from a subsequent inflammatory challenge highlighting its potential therapeutic for individuals with asthma.
Assuntos
Angiotensina I , Lipopolissacarídeos , Pulmão , Ovalbumina , Fragmentos de Peptídeos , Animais , Angiotensina I/uso terapêutico , Angiotensina I/farmacologia , Angiotensina I/administração & dosagem , Fragmentos de Peptídeos/farmacologia , Fragmentos de Peptídeos/uso terapêutico , Fragmentos de Peptídeos/administração & dosagem , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/imunologia , Ovalbumina/imunologia , Camundongos , Masculino , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Camundongos Endogâmicos BALB C , Inflamação/tratamento farmacológico , Eosinofilia/tratamento farmacológico , Eosinofilia/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Líquido da Lavagem Broncoalveolar/citologiaRESUMO
SUMMARY: It is known that diabetes mellitus has late complications, including microvascular and macrovascular diseases. Diabetes can affect bones through biochemical markers of bone structure, density, and turnover. This study aimed to biomechanically investigate the bone-protective effects of angiotensin 1-7 (Ang 1-7), one of the active peptides in the renin-angiotensin system, in rats with diabetes. Thirty male Wistar albino rats, three months old and weighing 250-300 g, were divided into four groups: diabetes, Ang 1- 7, diabetes plus Ang 1-7, and control. One month later, diabetes developed in rats; the rats were sacrificed, and their right femur was removed. Three-point bending biomechanical tests were performed on the femurs. The diabetic group had significantly higher bone fragility than the other groups (Pr >.05). Bone fragility was lower, and bone flexibility was higher in the Ang 1-7 groups (Pr>F value 0.05). As a result of our study, the effect of Ang 1-7 on the bones of rats with diabetes was investigated biomechanically. Ang 1-7 has a protective impact on the bones of rats with diabetes.
Se sabe que la diabetes mellitus tiene complicaciones tardías, incluyendo enfermedades microvasculares y macrovasculares. La diabetes puede afectar los huesos a través de los marcadores bioquímicos de la estructura, la densidad y el recambio óseo. Este estudio tuvo como objetivo investigar biomecánicamente los efectos protectores en los huesos de la angiotensina 1-7 (Ang 1-7), uno de los péptidos activos en el sistema renina-angiotensina, en ratas con diabetes. Treinta ratas albinas Wistar macho, de tres meses de edad y con un peso de 250-300 g, se dividieron en cuatro grupos: diabetes, Ang 1-7, diabetes más Ang 1-7 y control. Un mes después, se desarrolló diabetes en ratas; se sacrificaron los animales y se extrajo su fémur derecho. Se realizaron pruebas biomecánicas de flexión de tres puntos en los fémures. El grupo diabéticos tenía una fragilidad ósea significativamente mayor que los otros grupos (Pr > 0,05). La fragilidad ósea fue menor y la flexibilidad ósea fue mayor en los grupos Ang 1-7 (valor Pr>F 0,05). Como resultado de nuestro estudio, se determinó biomecánicamente el efecto de Ang 1-7 en los huesos de ratas con diabetes. Se concluye que Ang 1-7 tiene un impacto protector en los huesos de ratas diabéticas.
Assuntos
Animais , Masculino , Ratos , Fragmentos de Peptídeos/administração & dosagem , Sistema Renina-Angiotensina , Angiotensina I/administração & dosagem , Diabetes Mellitus Experimental , Fêmur/efeitos dos fármacos , Fenômenos Biomecânicos , Osso e Ossos/efeitos dos fármacos , Ratos Wistar , Modelos Animais de DoençasRESUMO
Angiotensin-(1-7) [Ang-(1-7)]/Mas receptor is a counter-regulatory axis that counteracts detrimental renin-angiotensin system (RAS) effects, especially regarding systemic inflammation, vasopressin (AVP) release, and hypothalamic-pituitary-adrenal (HPA) activation. However, it is not completely understood whether this system may control centrally or systemically the late phase of systemic inflammation. Thus, the aim of this study was to determine whether intracerebroventricular (i.c.v.) administration of Ang-(1-7) can modulate systemic inflammation through the activation of humoral pathways in late phase of endotoxemia. Endotoxemia was induced by systemic injection of lipopolysaccharide (LPS) (1.5 mg/kg, i.v.) in Wistar rats. Ang-(1-7) (0.3 nmol in 2 µL) promoted the release of AVP and attenuated interleukin-6 (IL-6) and nitric oxide (NO) levels but increased interleukin-10 (IL-10) in the serum of the endotoxemic rats. The central administration of Mas receptor antagonist A779 (3 nmol in 2 µL, i.c.v.) abolished these anti-inflammatory effects in endotoxemic rats. Furthermore, Ang-(1-7) applied centrally restored mean arterial blood pressure (MABP) without affecting heart rate (HR) and prevented vascular hyporesponsiveness to norepinephrine (NE) and AVP in animals that received LPS. Together, our results indicate that Ang-(1-7) applied centrally promotes a systemic anti-inflammatory effect through the central Mas receptor and activation of the humoral pathway mediated by AVP.
Assuntos
Angiotensina I/administração & dosagem , Angiotensina I/uso terapêutico , Endotoxemia/tratamento farmacológico , Hipotensão/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/uso terapêutico , Vasopressinas/metabolismo , Animais , Endotoxemia/sangue , Endotoxemia/complicações , Endotoxemia/genética , Regulação da Expressão Gênica , Hipotensão/sangue , Hipotensão/complicações , Hipotensão/genética , Inflamação/sangue , Inflamação/complicações , Inflamação/patologia , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Lipopolissacarídeos , Masculino , Concentração Osmolar , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/metabolismo , Ratos Wistar , Receptores Acoplados a Proteínas G/metabolismo , Sódio/sangue , Vasopressinas/genéticaRESUMO
NEW FINDINGS: What is the central question of this study? The central goal of this study was to understand the effects of central angiotensin-(1-7) on basal and osmotically stimulated water intake in rats. What is the main finding and its importance? This study demonstrated that central administration of angiotensin-(1-7) did not induce thirst in basal conditions but increased water intake after osmotic stimulation, such as water deprivation and salt loading. These results indicate a new function for this peptide, which, in turn, allows for future research on the mechanisms through which angiotensin-(1-7) influences osmotic thirst. Angiotensin-(1-7) [Ang-(1-7)] is generated by type 2 angiotensin-converting enzyme (ACE2) and binds to the MAS receptor. Although it is well known that Ang-(1-7) functionally antagonizes the effects of the classical renin-angiotensin system in several situations, the role of Ang-(1-7) in hydromineral homeostasis is not clear. The aim of this study was to assess the role of Ang-(1-7) on neuroendocrine responses to hyperosmolality in rats. Male Wistar rats were divided into the following three groups: control; 24 h of water deprivation (WD); and 24 h of salt loading (SL; 1.8% NaCl). Intracerebroventricular (i.c.v.) injections of Ang-(1-7) or vehicle were given to assess water intake and plasma concentration of vasopressin. Additionally, the brains from control and WD groups were collected to evaluate gene expression in the subfornical organ (SFO), paraventricular nucleus (PVN) and supraoptic nucleus (SON). It was found that i.c.v. Ang-(1-7) did not change water and salt intake in control rats; however, Ang-(1-7) increased water intake after WD and SL, with no change in salt intake. Plasma vasopressin was not changed by i.c.v. Ang-(1-7) in control or WD rats. Moreover, WD increased Mas gene expression in the SON and PVN, with no changes in Ace2 mRNA levels. In conclusion, Ang-(1-7) increases thirst after osmotic stimuli, indicating that a previous sensitization to its action is necessary. This finding is consistent with the increased Mas gene expression in the PVN and SON after water deprivation.
Assuntos
Angiotensina I/administração & dosagem , Ingestão de Líquidos/efeitos dos fármacos , Pressão Osmótica , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Órgão Subfornical/efeitos dos fármacos , Núcleo Supraóptico/efeitos dos fármacos , Sede/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2 , Animais , Injeções Intraventriculares , Masculino , Núcleo Hipotalâmico Paraventricular/metabolismo , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Ratos Wistar , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Cloreto de Sódio/administração & dosagem , Órgão Subfornical/metabolismo , Núcleo Supraóptico/metabolismo , Regulação para Cima , Vasopressinas/sangue , Privação de ÁguaRESUMO
We aimed to study the renal injury and hypertension induced by chronic intermittent hypoxia (CIH) and the protective effects mediated by angiotensin 1-7 [Ang(1-7)]. We randomly assigned 32 male Sprague-Dawley rats (body weight 180-200 g) to normoxia control, CIH, Ang(1-7)-treated normoxia, and Ang(1-7)-treated CIH groups. Systolic blood pressure (SBP) was monitored at the start and end of each week. Renal sympathetic nerve activity (RSNA) was recorded. CTGF and TGF-ß were detected by immunohistochemistry and western blotting. Tissue parameters of oxidative stress were also determined. In addition, renal levels of interleukin-6, tumor necrosis factor-α, nitrotyrosine, and hypoxia-inducible factor-1α were determined by immunohistochemistry, immunoblotting, and ELISA. TUNEL assay results and cleaved caspase 3 and 12 were also determined. Ang(1-7) induced a reduction in SBP together with a restoration of RSNA in the rat model of CIH. Ang(1-7) treatment also suppressed the production of reactive oxygen species, reduced renal tissue inflammation, ameliorated mesangial expansion, and decreased renal fibrosis. Thus, Ang(1-7) treatment exerted renoprotective effects on CIH-induced renal injury and was associated with a reduction of oxidative stress, inflammation and fibrosis. Ang(1-7) might therefore represent a promising therapy for obstructive sleep apnea-related hypertension and renal injury.
Assuntos
Injúria Renal Aguda/tratamento farmacológico , Angiotensina I/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Animais , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Rim/metabolismo , Rim/patologia , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
We aimed to study the renal injury and hypertension induced by chronic intermittent hypoxia (CIH) and the protective effects mediated by angiotensin 1-7 [Ang(1-7)]. We randomly assigned 32 male Sprague-Dawley rats (body weight 180-200 g) to normoxia control, CIH, Ang(1-7)-treated normoxia, and Ang(1-7)-treated CIH groups. Systolic blood pressure (SBP) was monitored at the start and end of each week. Renal sympathetic nerve activity (RSNA) was recorded. CTGF and TGF-β were detected by immunohistochemistry and western blotting. Tissue parameters of oxidative stress were also determined. In addition, renal levels of interleukin-6, tumor necrosis factor-α, nitrotyrosine, and hypoxia-inducible factor-1α were determined by immunohistochemistry, immunoblotting, and ELISA. TUNEL assay results and cleaved caspase 3 and 12 were also determined. Ang(1-7) induced a reduction in SBP together with a restoration of RSNA in the rat model of CIH. Ang(1-7) treatment also suppressed the production of reactive oxygen species, reduced renal tissue inflammation, ameliorated mesangial expansion, and decreased renal fibrosis. Thus, Ang(1-7) treatment exerted renoprotective effects on CIH-induced renal injury and was associated with a reduction of oxidative stress, inflammation and fibrosis. Ang(1-7) might therefore represent a promising therapy for obstructive sleep apnea-related hypertension and renal injury.
Assuntos
Animais , Masculino , Ratos , Injúria Renal Aguda/tratamento farmacológico , Angiotensina I/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Rim/metabolismo , Rim/patologia , Ratos Sprague-DawleyRESUMO
Shiga toxin 2 (Stx2)-producing enterohemorrhagic induced brain damage. Since a cerebroprotective action was reported for angiotensin (Ang)-(1-7), our aim was to investigate whether Ang-(1-7) protects from brain damage induced by Stx2-producing enterohemorrhagic Escherichia coli The anterior hypothalamic area of adult male Wistar rats was injected with saline solution or Stx2 or Stx2 plus Ang-(1-7) or Stx2 plus Ang-(1-7) plus A779. Rats received a single injection of Stx2 at the beginning of the experiment, and Ang-(1-7), A779, or saline was administered daily in a single injection for 8 days. Cellular ultrastructural changes were analyzed by transmission electron microscopy. Stx2 induced neurodegeneration, axonal demyelination, alterations in synapse, and oligodendrocyte and astrocyte damage, accompanied by edema. Ang-(1-7) prevented neuronal damage triggered by the toxin in 55.6 ± 9.5% of the neurons and the Stx2-induced synapse dysfunction was reversed. In addition, Ang-(1-7) blocked Stx2-induced demyelination in 92 ± 4% of the axons. Oligodendrocyte damage caused by Stx2 was prevented by Ang-(1-7) but astrocytes were only partially protected by the peptide (38 ± 5% of astrocytes were preserved). Ang-(1-7) treatment resulted in 50% reduction in the number of activated microglial cells induced by Stx2, suggesting an anti-inflammatory action. All these beneficial effects elicited by Ang-(1-7) were blocked by the Mas receptor antagonist and thus it was concluded that Ang-(1-7) protects mainly neurons and oligodendrocytes, and partially astrocytes, in the central nervous system through Mas receptor stimulation.
Assuntos
Angiotensina I/administração & dosagem , Infecções por Escherichia coli/prevenção & controle , Hipotálamo/patologia , Encefalite Infecciosa/induzido quimicamente , Encefalite Infecciosa/prevenção & controle , Fragmentos de Peptídeos/administração & dosagem , Toxina Shiga II/toxicidade , Animais , Infecções por Escherichia coli/induzido quimicamente , Infecções por Escherichia coli/patologia , Hipotálamo/efeitos dos fármacos , Encefalite Infecciosa/patologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Wistar , Escherichia coli Shiga Toxigênica/metabolismo , Resultado do TratamentoRESUMO
Angiotensin-(1-7) [Ang-(1-7)] develops its functions interacting with Mas receptor. Mas receptor was recently identified in the DRG and its activation by Ang-(1-7) resulted in peripheral antinociception against PGE2 hyperalgesia in an opioid-independent pathway. Nevertheless, the mechanism by which Ang-(1-7) induce peripheral antinociception was not yet elucidated. Considering that endogenous noradrenaline could induce antinociceptive effects by activation of the adrenoceptors the aim of this study was verify if the Ang-(1-7) is able to induce peripheral antinociception by interacting with the endogenous noradrenergic system. Hyperalgesia was induced by intraplantar injection of prostaglandin E2 (2µg). Ang-(1-7) was administered locally into the right hindpaw alone and after either agents, α2-adrenoceptor antagonist, yohimbine (5, 10 and 20 µg/paw), α2C-adrenoceptor antagonist rauwolscine (10, 15 and 20 µg/paw), α1-adrenoceptor antagonist prazosin (0.5, 1 and 2 µg/paw), ß-adrenoceptor antagonist propranolol (150, 300 and 600 ng/paw). Noradrenaline (NA) reuptake inhibitor reboxetine (30 µg/paw) was administered prior to Ang-(1-7) low dose (20 ng) and guanetidine 3 days prior to experiment (30 mg/kg/animal, once a day), depleting NA storage. Intraplantar Ang-(1-7) induced peripheral antinociception against hyperalgesia induced by PGE2. This effect was reversed, in dose dependent manner, by intraplantar injection of yohimbine, rauwolscine, prazosin and propranolol. Reboxetine intensified the antinociceptive effects of low-dose of Ang-(1-7) and guanethidine, which depletes peripheral sympathomimetic amines, reversed almost 70% the Ang-(1-7)-induced peripheral antinociception. Then, this study provides evidence that Ang-(1-7) induce peripheral antinociception stimulating an endogenous noradrenaline release that activates peripheral adrenoceptors inducing antinociception.
Assuntos
Analgésicos/metabolismo , Angiotensina I/metabolismo , Norepinefrina/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Antagonistas Adrenérgicos beta/administração & dosagem , Analgésicos/administração & dosagem , Angiotensina I/administração & dosagem , Animais , Dinoprostona/administração & dosagem , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Medição da Dor , Fragmentos de Peptídeos/administração & dosagem , Prazosina/administração & dosagem , Proto-Oncogene Mas , Ratos , Receptores Adrenérgicos beta/metabolismo , Ioimbina/administração & dosagemRESUMO
Skeletal muscle atrophy is a pathological condition characterized by the loss of strength and muscle mass, an increase in myosin heavy chain (MHC) degradation and increase in the expression of two muscle-specific ubiquitin ligases: atrogin-1 and MuRF-1. Angiotensin II (AngII) induces muscle atrophy. Angiotensin-(1-7) [Ang-(1-7)], through its receptor Mas, produces the opposite effects than AngII. We assessed the effects of Ang-(1-7) on the skeletal muscle atrophy induced by AngII. Our results show that Ang-(1-7), through Mas, prevents the effects induced by AngII in muscle gastrocnemius: the decrease in the fibre diameter, muscle strength and MHC levels and the increase in atrogin-1 and MuRF-1. Ang-(1-7) also induces AKT phosphorylation. In addition, our analysis in vitro using C2C12 myotubes shows that Ang-(1-7), through a mechanism dependent on Mas, prevents the decrease in the levels of MHC and the increase in the expression of the atrogin-1 and MuRF-1, both induced by AngII. Ang-(1-7) induces AKT phosphorylation in myotubes; additionally, we demonstrated that the inhibition of AKT with MK-2206 decreases the anti-atrophic effects of Ang-(1-7). Thus, we demonstrate for the first time that Ang-(1-7) counteracts the skeletal muscle atrophy induced by AngII through a mechanism dependent on the Mas receptor, which involves AKT activity. Our study indicates that Ang-(1-7) is novel molecule with a potential therapeutical use to improve muscle wasting associated, at least, with pathologies that present high levels of AngII.
Assuntos
Angiotensina II/farmacologia , Angiotensina I/farmacologia , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Angiotensina I/administração & dosagem , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/fisiopatologia , Cadeias Pesadas de Miosina/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Fosforilação/efeitos dos fármacos , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Antecedentes: Angiotensina [Ang-(1-9)] disminuye la presión arterial (PA) y el remodel amiento cardíaco en la hipertensión arterial experimental independiente de renina. No hay antecedentes sobre el efecto de Ang-(1-9) en la progresión de daño renal de ratas hipertensas por expansión de volumen (con renina baja). Objetivo: Determinar la participación de Ang-(1-9) en la progresión del daño renal en ratas hipertensas (DOCA-sal). Métodos: Se utilizaron ratas Sprague Dawley macho de 150 +/- 10 g uninefrectomizadas tratadas con DOCA (60mg/Kg/2 veces sem, im) por 4 semanas. Como controles (Sham) se usaron ratas uninefrectomizadas. Desde la 2a semana las ratas DOCA, con presión arterial sistólica (PAS) > 140 mmHg, recibieron vehículo o Ang-(1-9) [602 ng/Kg min] por 2 semanas (minibomba Alzet). Se evaluó la respuesta inflamatoria y el daño renal profibrótico por la presencia de macrófagos infiltrativos y de mio-fibroblastos intersticiales. Se determinó, además, la presión arterial sistólica (PAS), masa corporal (MC), masa del riñón derecho (MR) y masa renal relativa (MRR). Resultados: Se observó una disminución del daño renal en las ratas DOCA-sal, cuando recibieron Ang-(1-9), respecto a aquellas que no la recibieron, evidenciado por una significativa disminución de macrófagos infiltrativos y miofibroblastos en el intersticio renal. El bloqueo de los receptores Mas y AT2, no tuvieron efectos adicionales. Conclusion: En este modelo experimental, Ang-(1-9) disminuyó la hipertensión y redujo significativamente la infiltración de macrófagos y la aparición de miofibroblastos en el intersticio renal. Estos resultados son la primera evidencia de que Ang-(1-9) reduce la fibrosis túbulo-intersticial renal y el daño renal hipertensivo.
Angiotensin [Ang] - (1-9) decreases blood pressure (BP) and cardiac remodeling in renin independent hypertension. There are not studies about the effect of Ang- (1-9) in the progression of hypertensive renal damage by volume overload (low-renin). The aim of this study was to determine the effect of Ang- (1-9) on renal damage in volume overload hypertensive rats by (DOCA-salt rats). Methods: Male Sprague Dawley rats, 150 +/- 10 g, were uni-nephrectomized and treated with DOCA (60mg/Kg) 2 times per week, for 4 weeks. Uninephrec-tomized rats were used as controls (Sham). From the 2nd week on DOCA rats with systolic blood pressure (SBP)> 140 mmHg received vehicle or Ang- (1-9) [602 ng / kg min] for 2 weeks (Alzet minipump). Inflammatory and profibrotic renal damage was evaluated by the presence of infiltrating macrophages and interstitial myofibroblasts. Results: Compared to rats receiving vehicle renal damage in DOCA-salt rats decreased when they received Ang- (1-9), as evidenced by a significant decrease in infiltrating macrophages and myofibroblasts in the renal interstitium. Mas and AT2 receptor blockade had no additional effect. The SBP, body mass (BM), mass of the right kidney (MR) and relative renal mass (MRR) were also determined. Conclusion: in this experimental model, Ang-(1-9) decreased hypertension and significantly reduced macrophage infiltration and the appearance of myofibroblasts in the renal interstitium. These results are the first evidence that Ang-(1-9) reduces renal tubulointerstitial fibrosis and hypertensive renal damage.
Assuntos
Masculino , Animais , Ratos , Angiotensina I/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Hipertensão/tratamento farmacológico , Rim , Rim/patologia , Angiotensina I/farmacologia , Composição Corporal , Fibroblastos , Fragmentos de Peptídeos/farmacologia , Macrófagos , Pressão Arterial , Ratos Sprague-Dawley , Renina/sangueRESUMO
Angiotensin-(1-7) has been described as a new potential therapeutic tool for the treatment and prevention of metabolic disorders by regulating several pathways in visceral white adipose tissue (vWAT). The aim of this study was to access the proteins differentially regulated by Ang-(1-7) using proteomic analysis of visceral adipose tissue. Male mice were divided into three groups and fed for 60 days, with each group receiving one of the following diets: standard diet+HPßCD (ST), high fat diet+HPßCD (HFD) and high fat diet+Ang-(1-7)/HPßCD (HFD+Ang-(1-7)). Body weight, fat weight and food intake were measured. At the end of treatment, Ang-(1-7) induced a decrease in body and fat weight. Differential proteomic analysis using two-dimensional electrophoresis (2-DE) combined with mass spectrometry were performed. Results of protein mapping of mesenteric adipose tissue using 2-DE revealed the presence of about 450 spots in each gel (n=3/treatment) with great reproducibility (>70%). Image analysis and further statistical analysis allowed the detection and identification of eight proteins whose expression was modulated in response to HFD when compared to ST. Among these, two proteins showed a sensitive response to Ang-(1-7) treatment (eno1 and aldehyde dehydrogenase). In addition, three proteins were expressed statistically different between HFD+Ang-(1-7) and HFD groups, and four proteins were modulated compared to standard diet. In conclusion, comparative proteomic analysis of a mice model of diet-induced obesity allowed us to outline possible pathways involved in the response to Ang-(1-7), suggesting that Ang-(1-7) may be a useful tool for the treatment of metabolic disorders.
Assuntos
Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Angiotensina I/administração & dosagem , Angiotensina I/farmacologia , Dieta Hiperlipídica/efeitos adversos , Obesidade/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/farmacologia , Proteoma/análise , Administração Oral , Animais , Eletroforese em Gel Bidimensional , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos , Obesidade/induzido quimicamente , Obesidade/metabolismo , Proteoma/metabolismo , Proteômica , Aumento de Peso/efeitos dos fármacosRESUMO
Angiotensin-(1-7) and resveratrol have been described as new potential therapeutic tools on treating and preventing metabolic disorders. In the present study we aimed to evaluate the effect of an oral formulation of angiotensin-(1-7) [Ang-(1-7)] included in HPB-cyclodextrin and resveratrol (RSV), in modulation of sirtuin and renin-angiotensin system (RAS) in adipose tissue of mice treated with a high-fat diet (HFD). We observed that HFD+Ang-(1-7) and HFD+RSV groups presented marked decrease in the adipose tissue mass. Furthermore, these animals showed improved insulin-sensitivity and glucose tolerance as well as lower plasma levels of fasting glucose and lipids. The RT-PCR analysis revealed decreased expression of ACE and an increase of ACE2 [Ang-(1-7) marker] in group treated with resveratrol and also an increased expression of SIRT1 in groups that received Ang-(1-7). We showed for the first time that improved metabolic profile is associated with increased expression of GLUT4 and high expression of AMPK/FOXO1/PPAR-γ pathway in adipose-tissue. Finally, adipocyte primary cell-culture incubated with and without sirtuin and Ang-(1-7)/Mas antagonists pointed out for a cross-talking between RAS and sirtuins. We conclude that oral administration of Ang-(1-7) and RSV improved metabolic profile through a cross-modulation between RAS and Sirtuins.
Assuntos
Angiotensina I/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Gordura Intra-Abdominal/metabolismo , Obesidade/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Sirtuínas/metabolismo , Administração Oral , Animais , Antimetabólitos/administração & dosagem , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica , Intolerância à Glucose/tratamento farmacológico , Intolerância à Glucose/etiologia , Intolerância à Glucose/metabolismo , Hiperinsulinismo/tratamento farmacológico , Hiperinsulinismo/etiologia , Hiperinsulinismo/metabolismo , Resistência à Insulina , Gordura Intra-Abdominal/patologia , Lipólise , Masculino , Camundongos , Obesidade/tratamento farmacológico , Obesidade/etiologia , Cultura Primária de Células , Proto-Oncogene Mas , Sistema Renina-Angiotensina/efeitos dos fármacos , Resistina/sangue , Resveratrol , Sirtuínas/genética , Estilbenos/administração & dosagemRESUMO
We evaluated effects of chronic intracerebroventricular infusion of angiotensin (Ang)-(1-7) on cardiovascular and metabolic parameters in fructose-fed (FF) rats. After 6 weeks of fructose intake (10% in drinking water), Sprague-Dawley rats were subjected to intracerebroventricular infusion of Ang-(1-7) (200 ng/h; FF+A7 group) or 0.9% sterile saline (FF group) for 4 weeks with continued access to fructose. Compared with control rats, FF rats had increased mean arterial pressure and cardiac sympathetic tone with impaired baroreflex sensitivity. FF rats also presented increased circulating triglycerides, leptin, insulin, and glucose with impaired glucose tolerance. Furthermore, relative weights of liver and retroperitoneal adipose tissue were increased in FF rats. Glycogen content was reduced in liver, but increased in muscle. In contrast, fructose-fed rats subjected to chronic intracerebroventricular infusion of Ang-(1-7) presented reduced cardiac sympathetic tone with normalized mean arterial pressure, baroreflex sensitivity, glucose and insulin levels, and improved glucose tolerance. Relative weight of liver, and hepatic and muscle glycogen contents were also normalized in FF+A7 rats. In addition, FF+A7 rats had reduced mRNA expression for neuronal nitric oxide synthase and NR1 subunit of N-methyl-d-aspartate receptor in hypothalamus and dorsomedial medulla. Ang-(1-7) infusion did not alter fructose-induced hyperleptinemia and increased relative weight of retroperitoneal adipose tissue. There were no differences in body weights, neither in liver mRNA expression of phosphoenolpyruvate carboxykinase or glucose-6-phosphatase among the groups. These data indicate that chronic increase in Ang-(1-7) levels in the brain may have a beneficial role in fructose-fed rats by ameliorating cardiovascular and metabolic disorders.
Assuntos
Angiotensina I/uso terapêutico , Encéfalo/metabolismo , Carboidratos da Dieta/efeitos adversos , Frutose/efeitos adversos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/prevenção & controle , Fragmentos de Peptídeos/uso terapêutico , Angiotensina I/administração & dosagem , Angiotensina I/metabolismo , Animais , Barorreflexo/efeitos dos fármacos , Barorreflexo/fisiologia , Glicemia/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Carboidratos da Dieta/farmacologia , Modelos Animais de Doenças , Frutose/farmacologia , Glicogênio/metabolismo , Infusões Intraventriculares , Insulina/metabolismo , Síndrome Metabólica/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de RiscoRESUMO
UNLABELLED: Diabetes mellitus type 2 (DM2) is a disease with increasing importance in modern societies and insufficient treatment options. Pharmacological stimulation of insulin signaling, which is blunted in DM2, is a promising approach to treat this disease. It has been shown that activation of the angiotensin (Ang)-(1-7)/Mas axis of the renin-angiotensin system leads to an improved glucose uptake. In this study, we intended to evaluate, whether this effect could be exploited therapeutically. We first confirmed that Ang-(1-7) improves insulin signaling and glucose uptake in vitro in cultured cardiomyocytes. We then evaluated the therapeutic effect of a newly developed hydro-xypropyl-ß-cyclodextrin-based Ang-(1-7) nano-formulation in a novel transgenic rat model of inducible insulin resistance and DM2. The chronic administration of this compound prevented the marked elevation in blood glucose levels in these rats at a dose of 30 µg/kg, reversed the established hyperglycemic state at a dose of 100 µg/kg, and resulted in improved insulin sensitivity, reduced plasma insulin and decreased diabetic nephropathy. In conclusion, an oral Ang-(1-7) formulation reverses hyperglycemia and its consequences in an animal model of DM2 and represents a novel therapeutic option for the treatment of DM2 and other cardio-metabolic diseases. KEY MESSAGE: A novel rat model with inducible diabetes can be used to evaluate new therapies. Angiotensin-(1-7) is effective in an oral formulation packaged in cyclodextrine. Angiotensin-(1-7) is a promising antidiabetic drug.
Assuntos
Angiotensina I/administração & dosagem , Angiotensina I/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/prevenção & controle , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/uso terapêutico , Administração Oral , Angiotensina I/farmacologia , Animais , Animais Recém-Nascidos , Desoxiglucose/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Insulina/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fragmentos de Peptídeos/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
Duchenne muscular dystrophy (DMD) is the most common inherited neuromuscular disease, and is characterized by the lack of dystrophin, muscle wasting, increased transforming growth factor (TGF)-ß Smad-dependent signalling and fibrosis. Acting via the Mas receptor, angiotensin-1-7 [Ang-(1-7)], is part of the renin-angiotensin system, with the opposite effect to that of angiotensin II. We hypothesized that the Ang-(1-7)/Mas receptor axis might protect chronically damaged tissues as in skeletal muscle of the DMD mouse model mdx. Infusion or oral administration of Ang-(1-7) in mdx mice normalized skeletal muscle architecture, decreased local fibrosis and improved muscle function in vitro and in vivo. These positive effects were mediated by the inhibition of TGF-ß Smad signalling, which in turn led to reduction of the pro-fibrotic microRNA miR-21 concomitant with a reduction in the number of TCF4 expressing fibroblasts. Mdx mice infused with Mas antagonist (A-779) and mdx deficient for the Mas receptor showed highly deteriorated muscular architecture, increased fibrosis and TGF-ß signalling with diminished muscle strength. These results suggest that this novel compound Ang-(1-7) might be used to improve quality of life and delay death in individuals with DMD and this drug should be investigated in further pre-clinical trials.
Assuntos
Angiotensina I/farmacologia , Força Muscular/efeitos dos fármacos , Distrofia Muscular de Duchenne/metabolismo , Fragmentos de Peptídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Angiotensina I/administração & dosagem , Animais , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibrose , Humanos , Masculino , Camundongos , Camundongos Endogâmicos mdx , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/genética , Fragmentos de Peptídeos/administração & dosagem , Receptores de Superfície Celular/antagonistas & inibidoresRESUMO
Low angiotensin-(1-7) (Ang-(1-7)) concentration is observed in some cardiovascular diseases and exercise training seems to restore its concentration in the heart. Recently, a novel formulation of an orally active Ang-(1-7) included in hydroxy-propyl-beta-cyclodextrin (HPB-CD) was developed and chronically administered in experimental models of cardiovascular diseases. The present study examined whether chronic administration of HPB-CD/Ang-(1-7) produces beneficial cardiovascular effects in spontaneously hypertensive rats (SHR), as well as to compare the results obtained with those produced by exercise training. Male SHR (15-week old) were divided in control (tap water) or treated with HPB-CD/Ang-(1-7) (corresponding to 30µgkg(-1)day(-1) of Ang-(1-7)) by gavage, concomitantly or not to exercise training (treadmill, 10 weeks). After chronic treatment, hemodynamic, morphometric and molecular analysis in the heart were performed. Chronic HPB-CD/Ang-(1-7) decreased arterial blood pressure (BP) and heart rate in SHR. The inclusion compound significantly improved left ventricular (LV) end-diastolic pressure, restored the maximum and minimum derivatives (dP/dT) and decreased cardiac hypertrophy index in SHR. Chronic treatment improved autonomic control by attenuating sympathetic modulation on heart and vessels and the SAP variability, as well as increasing parasympathetic modulation and HR variability. Overall results were similar to those obtained with exercise training. These results show that chronic treatment with the HPB-CD/Ang-(1-7) inclusion compound produced beneficial effects in SHR resembling the ones produced by exercise training. This observation reinforces the potential cardiovascular therapeutic effect of this novel peptide formulation.
Assuntos
Angiotensina I/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Excipientes/administração & dosagem , Hipertensão/terapia , Fragmentos de Peptídeos/administração & dosagem , beta-Ciclodextrinas/administração & dosagem , 2-Hidroxipropil-beta-Ciclodextrina , Administração Oral , Angiotensina I/farmacocinética , Animais , Anti-Hipertensivos/farmacocinética , Pressão Sanguínea , Terapia Combinada , Avaliação Pré-Clínica de Medicamentos , Terapia por Exercício , Frequência Cardíaca , Hipertensão/fisiopatologia , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Fragmentos de Peptídeos/farmacocinética , Condicionamento Físico Animal , Ratos , Ratos Endogâmicos SHR , Pressão VentricularRESUMO
Angiotensin-(1-7) is a bioactive component of the renin-angiotensin system that is formed endogenously and induces nitric oxide release in several tissues. The L-arginine/NO/cyclic GMP pathway and ATP-sensitive K+ channels have been proposed as the mechanism of action for the peripheral antinociception of several groups of drug and endogenous substances, including opioids, non-steroidal analgesics, acetylcholine and others. The aim of the present study was to investigate the involvement of the L-arginine/NO/cGMP and KATP+ pathway on antinociception induced by angiotensin-(1-7). Paw pressure in rats was used to induce hyperalgesia via an intraplantar injection of prostaglandin E2 (2 µg/paw). Ang-(1-7) (2, 3 and 4 µg/paw) elicited a local peripheral antinociceptive effect that was antagonized by the nonselective NO synthase (NOS) inhibitor L-NOarg and the selective neuronal NOS (nNOS) inhibitor L-NPA. The selective inhibition of endothelial (eNOS) and inducible (iNOS) NOS by L-NIO and L-NIL, respectively, was ineffective at blocking the effects of a local Ang-(1-7) injection. In addition, the level of nitrite in the homogenized paw tissue, as determined by a colorimetric assay, indicated that exogenous Ang-(1-7) is able to induce NO release. The soluble guanylyl cyclase inhibitor ODQ and the specific blocker of ATP-sensitive K+ channels glibenclamide (40, 80 and 160 µg/paw) antagonized the Ang-(1-7) response. The results provide evidence that Ang-(1-7) most likely induces peripheral antinociceptive effects via the L-arginine/NO/cGMP pathway and KATP+ pathway activation.
Assuntos
Trifosfato de Adenosina/metabolismo , Analgésicos/farmacologia , Angiotensina I/farmacologia , GMP Cíclico/metabolismo , Canais KATP/metabolismo , Óxido Nítrico/metabolismo , Dor/tratamento farmacológico , Fragmentos de Peptídeos/farmacologia , Analgésicos/administração & dosagem , Angiotensina I/administração & dosagem , Animais , Arginina/metabolismo , Dinoprostona/antagonistas & inibidores , Dinoprostona/farmacologia , Relação Dose-Resposta a Droga , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Masculino , Dor/metabolismo , Medição da Dor , Fragmentos de Peptídeos/administração & dosagem , Ratos , Ratos WistarRESUMO
Angiotensin (Ang)-(1-7) has been described as an important tool on treating and preventing metabolic disorders. In this study, we aimed to evaluate the effect of an oral formulation of Ang-(1-7) included in hydroxypropylß-cyclodextrin (HPßCD/Ang-[1-7]) on hepatic function, steatosis, and on liver inflammatory markers expression in mice treated with a high-fat diet. Male FVB/N mice were divided into 4 groups and fed for 60 days, with each group receiving 1 of the following diets: standard diet+HPßCD, standard diet+Ang-(1-7)/HPßCD, high-fat diet+HPßCD, or high-fat diet+Ang-[1-7]/HPßCD. Body weight, food intake, and blood parameters, such as total cholesterol, triglyceride, alaninetransaminases, and aspartate transaminases, were evaluated. Immunohistochemical analyses were performed for inflammatory markers tumor necrosis factor-α and interleukin-6. Expression of angiotensin converting enzyme, angiotensin-converting enzyme-2, interleukin-1ß, tumor necrosis factor-α, interleukin-6, transforming growth factor-ß, acetyl-CoA carboxylase, carbohydrate-responsive element-binding protein, peroxisome proliferator-activated receptor-γ, and sterol regulatory element-binding proteins-1c was evaluated by quantitative real-time polymerase chain reaction. The major findings of our study included reduced liver fat mass and weight, decreased plasma total cholesterol, triglyceride, and alaninetransaminase enzyme levels in the oral Ang-(1-7)-treated groups compared with the control groups. These results were accompanied by a significant reduction in tumor necrosis factor-α and interleukin-6 mRNA expression in the liver. Analyses of liver adipogenesis-related genes by quantitative real-time polymerase chain reaction showed that acetyl-CoA carboxylase, peroxisome proliferator-activated receptor-γ, and sterol regulatory element-binding proteins-1c mRNA expression were significantly suppressed. In conclusion, we observed that treatment with Ang-(1-7) improved metabolism and decreased proinflammatory profile and fat deposition in liver of mice.
Assuntos
Angiotensina I/farmacologia , Fígado Gorduroso/prevenção & controle , Inflamação/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Administração Oral , Angiotensina I/administração & dosagem , Animais , Química Farmacêutica , Dieta Hiperlipídica , Interleucina-6/fisiologia , Masculino , Camundongos , Fragmentos de Peptídeos/administração & dosagem , Proteína de Ligação a Elemento Regulador de Esterol 1/fisiologia , Fator de Necrose Tumoral alfa/fisiologiaRESUMO
Obesity is characterized by a pro-inflammatory state commonly associated with type 2 diabetes and fat-liver disease. In the last few years, different studies pointed out the role of Angiotensin (Ang)-(1-7) in the metabolic regulation. The aim of the present study was to evaluate the effect of oral-administration of Ang-(1-7) in metabolism and inflammatory state of high-fat feed rats. Twenty-four male Sprague Dawley rats were randomized into three groups: High Fat Diet (HFD); Standard Diet (ST); High Fat Diet+Angiotensin-(1-7) [HFD+Ang-(1-7)]. Glycemic profile was evaluated by glucose tolerance and insulin sensitivity tests, plasmatic glucose and insulin. Cholesterol, HDL and triglycerides analyses presented lipidic profile. RT-PCR evaluated mRNA expression to ACE, ACE2, resistin, TLR4, IL-6, TNF-α and NF-κB genes. The main results showed that oral Ang-(1-7) decreased body weight and abdominal fat-mass. In addition, HFD+Ang-(1-7) treated rats presented enhanced glucose tolerance, insulin-sensitivity and decreased plasma-insulin levels, as well as a significant decrease in circulating lipid levels. These alterations were accompanied by a marked decreased expression of resistin, TLR4, ACE and increased ACE2 expression in liver. Furthermore, Ang-(1-7) decreases phosphorylation of MAPK and increases NF-κB expression. These alterations diminished expression of interleukin-6 and TNF-α, ameliorate inflammatory state in liver. In summary, the present study showed that oral-treatment with Ang-(1-7) in high-fat feed rats improved metabolism down-regulating resistin/TLR4/NF-κB-pathway.
Assuntos
Angiotensina I/farmacologia , Inflamação/prevenção & controle , Fígado/efeitos dos fármacos , Obesidade/prevenção & controle , Fragmentos de Peptídeos/farmacologia , Angiotensina I/administração & dosagem , Angiotensina I/metabolismo , Animais , Glicemia/efeitos dos fármacos , Colesterol/sangue , Dieta Hiperlipídica , Teste de Tolerância a Glucose , Inflamação/tratamento farmacológico , Insulina/sangue , Resistência à Insulina , Lipoproteínas HDL/sangue , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Obesidade/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Ratos , Ratos Sprague-Dawley , Resistina/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Triglicerídeos/sangueRESUMO
The ß-adrenergic blockers and antagonists of the renin-angiotensin system (RAS) are among the drugs that present better results in the control of cardio-metabolic diseases. The aim of the present study was to evaluate the effect of the association of the ß-blocker, atenolol, and an oral formulation of Ang-(1-7) on lipid metabolism in spontaneously hypertensive rats (SHR). The main results showed that SHR treated with oral formulation of Ang-(1-7) in combination to atenolol have an improvement of lipid metabolism with a reduction of total plasma cholesterol, improvement of oral fat load tolerance and an increase in the lipolytic response stimulated by the ß-adrenergic agonist, isoproterenol, without modification of resting glucose or insulin sensitivity in adipocytes. In conclusion, we showed that administration of an Ang-(1-7) oral formulation in association with a ß-blocker induces beneficial effects on dyslipidemia treatment associated with hypertension.